Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Qual é a frequência média em MHz para a licença de Eastville, Virginia?
 ###Tabelas: CREATE TABLE competition_timeline (competition_timeline_id AUTO_INCREMENT PRIMARY KEY, Competition VARCHAR, 1970–71 VARCHAR, 1971–72 VARCHAR, 1972–73 VARCHAR, 1973–74 VARCHAR, 1974–75 VARCHAR, 1975–76 VARCHAR, 1976–77 VARCHAR, 1977–78 VARCHAR, 1978–79 VARCHAR, 1979–80 VARCHAR, 1980–81 VARCHAR, 1981–82 VARCHAR, 1982–83 VARCHAR, 1983–84 VARCHAR, 1984–85 VARCHAR, 1985–86 VARCHAR, 1986–87 VARCHAR, 1987–88 VARCHAR, 1988–89 VARCHAR, 1989–90 VARCHAR, 1990–91 VARCHAR, 1991–92 VARCHAR, 1992–93 VARCHAR, 1993–94 VARCHAR, 1994–95 VARCHAR, 1995–96 VARCHAR, 1996–97 VARCHAR, 1997–98 VARCHAR, 1998–99 VARCHAR, 1999–00 VARCHAR, 2000–01 VARCHAR, 2001–02 VARCHAR, 2002–03 VARCHAR, 2003–04 VARCHAR, 2004–05 VARCHAR, 2005–06 VARCHAR, 2006–07 VARCHAR, 2007–08 VARCHAR, 2008–09 VARCHAR, 2009–10 VARCHAR, 2010–11 VARCHAR, 2011–12 VARCHAR) CREATE TABLE 1971_isle_of_man_production_500_cc_tt_final_standings (1971_isle_of_man_production_500_cc_tt_final_standings_id AUTO_INCREMENT PRIMARY KEY, Rank INT, Rider VARCHAR, Team VARCHAR, Speed VARCHAR, Time VARCHAR) CREATE TABLE singles:_6_5_titles_1_runner-up (singles:_6_5_titles_1_runner-up_id AUTO_INCREMENT PRIMARY KEY, Outcome VARCHAR, Year INT, Championship VARCHAR, Surface VARCHAR, Opponent in the final VARCHAR, Score in the final VARCHAR) CREATE TABLE scoring_format (scoring_format_id AUTO_INCREMENT PRIMARY KEY, From INT, To INT, Goal INT, Round 1 VARCHAR, Round 2 VARCHAR, Round 3 VARCHAR, Round 4 VARCHAR, Round 5 VARCHAR, Round 6+ VARCHAR) CREATE TABLE repeaters (repeaters_id AUTO_INCREMENT PRIMARY KEY, Call sign VARCHAR, Frequency MHz INT, City of license VARCHAR, ERP W INT, Class VARCHAR, FCC info VARCHAR)  
SELECT AVG Frequency MHz FROM repeaters WHERE City of license = eastville, virginia